UPSTREAM: docs: correct documentation for %pK

Current documentation indicates that %pK prints a leading '0x'. This is
not the case.

Correct documentation for printk specifier %pK.

Signed-off-by: Tobin C. Harding <me@tobin.cc>
(cherry picked from commit 553d8e8b107159088cc4e2855a2bd9a358365e3f)
Signed-off-by: Sandeep Patil <sspatil@android.com>

Bug: 78533979
Test: n/a
Change-Id: I055e337b876fa3235c65182fbe6b85f17da4295f